Season chicken breasts with salt and pepper.

Dredge chicken in flour and shake off excess.

In a large skillet over medium-high heat, melt 2 tablespoons of butter with the olive oil. When the butter and oil start to sizzle, add the chicken and cook for about 3 minutes per side, or until browned. Remove the chicken and set aside.

Add the lemon juice, chicken stock, and capers to the pan. Bring the mixture to a boil, scraping up the browned bits from the pan for extra flavor.

Return the chicken to the pan and simmer for 5 minutes.

Remove the chicken to a platter. Add the remaining 2 tablespoons of butter to the sauce and whisk vigorously.

Pour the sauce over the chicken, garnish with parsley, and serve.